Angiogenesis, Inflammation, and Oxidative Stress: Interrelationships in Autoimmune Thyroid Diseases

Autoimmune thyroid diseases (AITD) are based on reactivity to thyroid self-antigens, resulting in varying degrees of persistent inflammation and glandular hyperplasia. The aim of this study was to investigate the interplay between angiogenesis, inflammation, and oxidative stress in patients with AITD. The study included patients with AITD, divided into a group with Hashimoto's thyroiditis (HT) and a group with Graves' disease (GD), as well as healthy controls. The results showed that subjects with GD had significantly higher concentrations of angiopoietin-2 (Ang-2) compared to those with HT and the healthy controls (p < 0.001). Inflammatory parameters (C-reactive protein (CRP), the systemic inflammatory immune response index (SII), and the CRP/albumin ratio (CRP/alb)) were higher in both AITD groups (p < 0.001). Oxidative stress parameters were more pronounced in AITD, while the activity of antioxidant enzymes was reduced. Ang-2 positively correlated with H₂O₂ (r = 0.394, p = 0.006) and NO (r = 0.519, p = 0.001) in HT, as well as with O₂^- (r = 0.232, p = 0.009) and TBARS (r = 0.190, p = 0.038) in GD, while in GD it showed a negative correlation with SOD (r = -0.426, p = 0.012) and CAT (r = -0.534, p = 0.008). Thus, angiogenesis, inflammation, and oxidative stress are interconnected processes in AITD, which may have significance for further understanding of the disease and the development of therapeutic approaches.